A phosphide is commonly chosen for a flame retardant to replace halogen compounds in a halogen-free composition. Moreover, in order to reduce the phosphor content, aluminum hydroxide is employed to meet the UL-94 V0 fire rating. Aluminum hydroxide is also employed in a halogen-free and phosphor-free composition to meet the UL-94 V0 fire rating.
As for the materials of organic substrate, except for bismaleimide triazine (BT) resin, epoxy-based fire retardant resins generally have a Tg of about 180° C. measured by a thermal mechanical analyzer (TMA). Therefore, to improve the flame retardancy, flame-retardant inorganic powders or resins are additionally incorporated.
Accordingly, what is needed in the art is an eco-friendly resin with high thermal-resistance and low-dielectric-constant for advances in high-frequency devices.